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The TPM improaement plan  85


                   Data for fouiv-week period
                   Over a recent four-week period the following OEE results were obtained:

                   Week        OEE     =    Availability   x   Pevformance   x   Quality
                                ("/.I          ("/I            rate  (Yo)      rate (YO)
                      9        44.6    =       65.0     X       70.0      X     98.0
                      2        43.8    =       58.0     X       77.0      X     98.0
                      3        36.7    =       47.0     X       80.0      X     97.5
                      4        31.9    =       44.7     X       72.5      X     98.5
                   Average     39.4    =       53.7     X       74.9      X     98.0
                   Best of best OEE and potential benefit
                   The best of  best OEE can now be calculated. In addition, if  the hourly rate of
                   added value is taken to be €100, the annual benefit (45-week year) of moving
                   from the current average OEE of  39.4 per cent to the best of best can be found.
                        Best of  best OEE  = availability x performance x quality
                                        = 65.0 x 80.0 x 98.5 = 51.2%

                   Potential loading hours per year = 114 x 45 = 5130
                   At 39.4% OEE, value added per year = 0.394 x 5130 x €100  = €202 122
                   At 51.2% OEE, value added per year = 0.512 x 5130 x €100 = €262 656

                   Therefore, a benefit of  €60 534 is possible by consistently achieving best of
                   best through tackling the six losses  using the nine-step TPM improvement plan.

                   Step 3 Assessment of the six big losses

                   The importance of  understanding and tackling the six big losses cannot be
                   over-emphasized! They were listed in Chapter 3 and illustrated by the iceberg
                   analogy in Figure 3.14, repeated here as Figure 5.5. The six losses are as follows:

                      0  Breakdowns
                      e  Set-up and adjustment
                      0  Idling and minor stoppages
                      0  Running at reduced speed
                      0  Quality defect and rework
                      0  Start-up losses
                   These are elaborated in Figures 5.7-5.12  in terms of  the relationship of  these
                   losses to the OEE.
                      Figure 5.6 shows the losses as a fishbone cause and effect diagram. This
                   formula  is used  by  the TPM  core team  as a brainstorming  tool to list all
                   possible causes and reasons for each of  the six loss categories.
                      We  will develop a detailed definition in later chapters regarding the four
                   levels of  control referred to under each of  the six losses in Figures 5.7-5.12.
                   However, in order to give an early indication a definition is as follows:
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